1996—2016年中国城市群建成区绿地率区域差异实证分析

An Empirical Analysis of Regional Difference of Green Space Rate of Built Districts in China's Urban Agglomeration from 1996 to 2016

摘?要?随着新型城镇化进程的推进,中国进入了以城市群为主体的区域发展格局,城市绿地建设成为城市发展的重要组成部分。探明不同层级城市群绿地建设水平区域差异,可为制定差异化绿地建设政策提供理论依据。综合应用数理统计、差异指数分析等方法,研究1996—2016年我国国家级、区域性、地区性三大层级共20个城市群建成区绿地率的总体差异特征,并对其进行构成分解。结果表明:首先在时空分布上,建成区绿地率具有明显的区位优势,但存在显著的层级性差异,低速发展集聚趋势加剧,与城市群发育程度不协调;其次在差异演变上,建成区绿地率区域差异在总体、不同层级均为下降趋势,不同层级上差异缩小的波动程度不同,呈"地区性>国家级>区域性"的特征;最后是差异分解上,建成区绿地率总体差异主要由层级内差异引起,其中国家级城市群内差异最大,对总体差异的影响度逐步加强,而层级间差异对总体差异的贡献度略有提升。

As the core area with the most vitality and potential in China’s future urban development pattern, urban agglomerations have been facing increasingly serious ecoenvironmental problems. Paying attention to the urban green space construction is of great significance for realizing the transformation of urban agglomerations from “problem concentration areas” to “sustainable development areas” and promoting the level of urban green space construction throughout the country. However, in the process of improving the level and reshaping the distribution pattern of urban green construction, there are significant differences among urban agglomerations. Therefore, exploring the differences of green space among urban agglomerations has the practical significance to clarify the main problems in the construction of urban green space clearly, and improve the urban green space construction of urban agglomerations. Exploring the regional differences and evolutionary characteristics of urban green space has gradually become a hot spot for domestic scholars, and the research results have become more and more abundant. However, previous studies have not considered the background of the re-clustering development of cities in China, nor have they been able to penetrate into the perspective of urban agglomeration research, nor can they continuously explore the regional differences of urban green space construction in China. Therefore, this paper chooses the green rate of built district in urban agglomerations in China from 1996 to 2016 as a research index to characterize the urban green space construction level. Using the methods of mathematical statistics and difference index analysis to reveal overall difference characteristics of green rate of built district in 20 urban agglomerations in China and decompose the difference composition, this study can break the spatial classification model of past solidification and enrich the research perspectives and methods of regional differences in urban green space construction. The purpose of this study is to provide scientific basis for the formulation of relevant green space construction as well as development policies for different urban agglomerations. The results show: 1. in the spatial-temporal distribution pattern, urban agglomeration has turned into the core area for the rapid growth of green space construction. The green rate of built district in urban agglomeration has been rising continuously. Although the growth rate has gradually slowed down, it still presents advantages over the country. The difference in growth of urban agglomerations at different levels is more obvious. 2. In the evolution of differences, the differences of green rate of built district among the urban agglomerations in China are shrinking, but the degree of fluctuation of absolute differences is stronger than the relative differences. The differences in urban agglomerations at different levels are gradually slowing down, and there exists significant hierarchical differences in the degree of volatility. The degree of fluctuation of the difference in the different levels of urban agglomeration exhibits different characteristics, and it is characterized by “local > national > regional”. 3. From the perspective of difference decomposition, the spatial distribution differences of green rate of built district will exist in China for a long time, and the overall differences of green space construction are mainly caused by the differences within the hierarchy. The difference within the national-level urban agglomeration is the greatest, and the contribution of the difference among different levels is generally decreased. The contribution of local urban agglomerations to the overall differences shows a decreasing trend. In the period of promoting the new urbanization process in China, there are variously important issues that need to be solved urgently in the implementation of the integrated development strategy of urban green space construction. For example, we should break the boundaries of administrative divisions, analyze the characteristics of regional differences and evolution of green space development in urban agglomerations from multiple perspectives, and regulate green space construction planning with the spatial radiation effect of urban agglomerations. We should promote the study of regional coordinated development strategies and optimize the green space construction pattern of urban agglomerations, vigorously improve the government-led urban cluster development strategy, clarify the environmental background of urban agglomeration green space construction, differentiate the urban agglomerations in different green land construction development stages and needs and strengthen the overall advantages of green space construction. It is also necessary to establish a coordination mechanism for urban agglomeration green space construction and implement a comprehensive level planning and regulation strategy. Priority should be given to promoting the coordinated development ability of national urban agglomerations and improving the quality of green space construction in each urban agglomeration. The green space construction mode of regional urban agglomeration needs to be changed. The next step is to weaken its dependence on resources and strengthen the orientation of green space construction objectives in terms of policies and regulations. The strong momentum of green space construction and development of local urban agglomerations needs to be maintained, and the next step should focus on promoting the goal of highly integrated green space construction.